1. Field of the Invention
This invention relates to an apparatus for controlling weft inserting in an air jet loom, a water jet loom or the like, and more particularly, to an apparatus for controlling the pressure of fluid for weft inserting.
2. Description of the Prior Art
In a jet loom, there is a known disclosure relating to an apparatus for controlling weft inserting which calculates, in particular, a pressure value of fluid provided in a nozzle for weft inserting as well as a weft inserting condition on the basis of textile conditions such as weft types, weft size, woven density, textile width and woven texture, and adjusts the pressure of the fluid on the basis of the calculated pressure value. (Japanese Patent Public Disclosure (KOKAI) Nos. 63-21951 and 63-21953)
In this conventional apparatus for controlling weft inserting, the textile conditions to be used for calculation are the values determined according to the set-up textile conditions such as a weft type: spun yarn-count #50, a fabric width: 150 cm, and a woven density: 50 pcs/in.
In case of the same type of weft, the easy flyability and cuttability thereof would seem to be all the same, but this is not the case. In other words, if the production lots in a weft production process even in the same type of weft are mutually different, the dispersion with respect to the easy flyability and cuttability cannot be avoided since there is some unevenness of the weft in size or some fluff. It cannot be said that the dispersions in easy flyability and cuttability are strictly the same even in the same type of weft.
Such a thing can be said with other things than the dispersion of weft while the weft is manufactured. For example, the same thing can be said with performance of the devices relating to weft inserting such as a weft inserting nozzle, a reed and a length measuring storage device. As described above, the easy flyability and cuttability of weft as well as the performance of a weft insertion device are not such definite values as described above but indefinite values such as "easy to fly", "hard to fly", "easy to be cut" and "hard to be cut".
Since the injection timing of fluid for weft inserting and the operation timing of an engagement pin are not significantly influenced by the preceding indefinite values, there are no problems even in calculating these timing values by using a prior art. In particular, the injection pressure of the weft inserting fluid is, however, largely influenced by the preceding indefinite values.
In the preceding conventional apparatus for controlling weft inserting, however, any preceding indefinite values are not taken into consideration, and therefore, no accurate weft inserting injection pressure suitable to any actual weft and any weft insertion device could be calculated.